Contact Information

Global Publishing Network, Inc.
P. O. Box 31471
Palm Beach Gardens, FL 33420

Phone: 561-625-6300
Fax: 561-626-9640

Database: What is SQL?

Structure Query Language. Relational database programs, such as Oracle or MySQL, recognize this language. A user can write SQL scripts that create databases and tables, insert data into databases, and draw that data back out. Each database program utilizes a different version of SQL, but most are very similar, so once you learn SQL on one database, it is not difficult to use it on others.

There are 2 types of database:

Flat File: Everything is stored in one big table - like a telephone directory or a spreadsheet.
Relational: Similar data is grouped together into separate tables, for example, a Library Database may have:

  • a table storing Customers Details
  • a table storing Book Categories
  • a table storing Book Details
  • a table storing Lending Records

The tables are related together using a unique identifier for each record.

  • BookID (unique field)
  • BookName text field

A relational database minimizes data errors, redundancy and duplication since each record needs to be stored only once. It also promotes data integrity/accuracy which means data storage costs are minimized.